1. Field of the Invention
This invention relates to footwear having an upper and a lower, more specifically to a cushion structure integrated as part of the lower.
2. Description of the Related Art
The modern shoe is a combination of various components which all have a critical function in the performance of the shoe. Each component must work closely as a system for the support, comfort, and protection of the user's foot. There are specialized shoes designed for athletes in very different activities from: road running, hiking, general fitness, and basketball. Each of these shoes are designed to provide a special blend of performance related to traction, support, comfort, and protection. Shoes are also designed for the physical characteristics of the wearer such as the user's weight, shoe size and gait (i.e. over pronation, supination, flat-footed). Specifically, the weight, cushioning, lateral stability characteristics of a shoe can be a strong determinant of performance because they may directly impact an athlete's speed, endurance, and sure-footing.
There has been many attempts to create cushion devices in the shoe to improve shock absorption yet these efforts have produced insufficient lateral stability or unnecessarily heavy shoes that are inadequate for serious athletes and active people.
Although foregoing efforts have met with varying degrees of success, there remains an unresolved need for a lower for athletic footwear with improved shock absorption, lateral stability, and low weight. The problem is that previous shoe technology does not provide the level of shock and shear force absorption required by the wearer for demanding applications without an unacceptable thicker sole, greater weight, or loss of lateral stability. There are additional issues to consider such as changes to the bending and twisting characteristics of the shoe as shock absorbing materials are used that might compromise measures to control pronation or other undesirable walking or running characteristics of the wearer.